This is a vintage Norman Rockwell Mother's Day art collectors porcelain plate from the Rockwell Society of America 1987 and made by Edwin M. Knowles Co. right here in the USA, one of the oldest fine china producers in America. This is called "Grandma's Surprise" and is a numbered limited edition plate.  Plate number 6662H.
Great color and content on plate. It is 8 1/2 inches diameter. 
Has box and certificates, kept in a smoke free home.